So, I only come back here about once per fortnight or thereabouts, but when I do I always have anywhere from 10 to 30 gifts in my inventory. I don't even know that many people here (which hopefully rules out stalking). Has there been a surge of the popularity of gifting around Subeta recently that I missed (meaning, are people just sending out more gifts to different places, period?), or am I just getting hit by random gift-flailing more frequently because of my name?

Luminaire just passed so it could have something to do with that, since that's when people anon-gift the most. And the gifting system got a revamp within the last month, so maybe people decided to test it out on you.

I'm pretty sure there's also an achievement for gift giving, but I'm not sure if it's active anymore.

People also get tasks to send gifts for Major Drills quests, maybe you are friends with people who are sending them to you?

Alright then. That's good to know. Ty guys.

Were the items sent via gift box? You can get up to 5 things in a single box now. If the gifts are anon (and unwanted) there's also an option to accept from friends only.

To expand on what others have already said, you can also go into your preferences under "Options" and check to turn off accepting items from non-friends.